1. Field of the Invention
The present invention relates to an infrared ear thermometer which is inserted into an external ear canal and detects an infrared radiation to estimate a subject's body temperature, and a temperature state estimation method, an information notification method, and a measurement operation management method thereof.
2. Description of the Related Art
An infrared ear thermometer measures a dose of infrared ray radiated from an ear drum to determine a body temperature. A temperature detection unit of the infrared ear thermometer is constituted by an infrared sensor which captures an infrared radiation and a temperature sensor which measures the temperature of the sensor itself, and measures a target temperature by using output signals from the infrared sensor and the temperature sensor. As an ideal measurement condition, it is required that the temperature of the infrared sensor and the temperature of the temperature sensor are equal to each other. However, in actual use, these temperatures are different from each other, and measurement body temperature accuracy is deteriorated. In particular, when an environment temperature (atmospheric temperature) at which the clinical thermometer is placed sharply changes before and after the measurement, different heat flows are generated from the clinical thermometer to the infrared sensor and the temperature sensor. A temperature difference between the sensors is generated. As a result, the body temperature measurement value has an error.
For this reason, in a conventional clinical thermometer, in measuring a body temperature by detecting an environment temperature, when the environment temperature is different from a normal room temperature, the environment temperature is checked to see if it is stabilized and whether the body temperature can be measured. When the environment temperature is detected as described above, in the prior art, the environment temperature and a change in the environment temperature are detected by a change in temperature of the temperature sensor of the clinical thermometer. Furthermore, a temperature measurement value is also corrected in consideration of the environment temperature.
However, when a change in environment temperature is detected by using a change in temperature of the temperature sensor of the clinical thermometer, even though the change of the temperature sensor is converged in a state in which the temperature of the temperature sensor and the temperature of the infrared sensor are different from each other, a measurement error is not converged, and the temperature measurement value has an error. When the temperature measurement value is corrected in consideration of the environment temperature, accurate correction cannot be performed in a state in which the environment temperature changes.